This invention relates generally to automotive air conditioning refrigerating systems, and, in particular, to a refrigerant compressor having an electromagnetic clutch for selectively coupling the compressor with an automobile engine.
It is conventional practice to drive the refrigerant compressor of an automotive air conditioning refrigerating system by the engine of the car. To this end, automobile air-conditioning system includes an electromagnetic clutch assembled on the refrigerating compressor. One of the clutch elements of the clutch includes a pulley coupled by a belt with the automobile engine of and is driven by the engine. When the other clutch element is magnetically attracted to the one of the clutch elements, the compressor is driven by the engine. Such an arrangement is described, for example, in U.S. Pat. Nos. 3,082,933 and 3,044,594.
As is known, a significant amount of electric power is consumed in the use of the automotive air conditioning refrigerating system to operate the electromagnetic clutch, blower, and other electric parts of the refrigeration system. This electric power is typically supplied from the car battery. Therefore, the use of the automobile air conditioning system often produces an undesired excessive load on the automobile battery.
In a typical automobile equipped with air conditioning, the electrical charging system for the battery, which is mounted on the car comprises an AC generator driven by the car, a rectifier, and a voltage controller. In the use of the automotive air conditioning refrigerating system, the usual electrical charging system may be insufficient to compensate for the substantial additional electric power consumption. Accordingly, an electric charging system of a high capacity must often be substituted for the usual electrical charging device of the car at the time of installation of the air conditioning refrigerating system. This adds significantly to the installing operation and to the cost of the system.